The timing could hardly be stranger. Just as the country is winding up to mark the centenary of the outbreak of World War One, rugby's most conspicuous commemoration of the conflict is reaching the end of the line.

Bristol's Memorial Ground, inaugurated in 1921 to mark the memory of the club's fallen - as well as 13 players, many members died in action - will stage its last match tonight when Bristol play London Welsh in the second leg of their Championship final.

There's a logic, given that Stephen Lansdown owns both clubs, in moving across the city to share the frankly superior facilities at Ashton Gate, Bristol City's ground. But it represents the end of 125 years of rugby in the same corner of Bristol.

Before the Mem was built, the club shared the county cricket pitch at Neville Road, and it spent a couple of years renting a ground at Radnor Road. None was more than a few minutes' walk from the Mem.

The land on which the ground was built was previously known as Buffalo Bill's Field in honour of a visit by the nineteenth century American showman. It had some rugby history - Chris Ducker's fine centenary history Rugby Bristol Fashion records that the club rented it for a year in 1901 to provide a ground for some of the city's proliferating junior clubs.

The land had been used as allotments during the war, but was released in 1920. Fundraising was handled by a citywide committee including octogenarian Henry Harding - whose great-grandson Richard would play scrum-half with distinction for both club and country in the 1980s. Costs, eventually £26,000, rose when a layer of limestone was discovered below the ground and levelling became that much tougher. But it was completed in a year and dedicated, in an inscription at the main gate 'In proud and grateful Memory of the services rendered for their Country in the Great War by the Rugby Football Players of Bristol'. A further commemorative tablet was added after the Second World War.

Bristol, led by international centre Len Corbett, beat Cardiff 19-3 on the ground's opening day, September 14, 1921. The crowd was reported as the largest to have watched club rugby in the city. The ground's impact on the club's appeal was immediate - Ducker records that membership more than quadrupled in the first season, while gate receipts set a record not matched until the early 1970s.

The ground has come down to us today as a gloriously eclectic range of structures more than making up in character and memories what they lack in architectural unity. Like other notable sporting mishmashes - Southampton's Dell and Swansea City's Vetch Field come to mind - each building reflected a stage in the history of the club and a response either to prosperity or to simple pressures for improved accommodation.

Idiosyncrasy extended beyond the structures. Fans asked about their memories are as likely to talk of the cat and the corgis once to be seen frequenting the ground on match days and the showers of rust which fell from the roof of one of the former stands whenever the ball was kicked onto it, as of great matches and players.

But it has also been one of the great English rugby venues. It was appropriate that both the first and the last matches there should have been against Welsh clubs, since Bristol's history was defined as much by cross-border contacts - a natural consequence of their location - as by the rest of England.

Bristol were often to be found at the forefront of attempts to extend Anglo-Welsh links - they wanted, for instance, to help turn Wales's Floodlit Alliance into a cross-border tournament in the 1960s, but were slapped down by the RFU.

They were one of the few English clubs who automatically commanded Welsh respect, particularly in the late 1950s when John Blake's teams played with a dash and imagination which represented a novelty in the defensively-minded game of the time. The large crowds of those years were likely to include veterans of great earlier days like Corbett or hooker Sam Tucker, whose often-recounted retelling of his flight from Filton to Cardiff as an emergency late call-up for the Wales v England match in 1930 could - Bristolian Daily Telegraph correspondent John Mason recalled - "command total silence in the old bar".

Nor was that the limit of the club's contribution to the national cause. There was a Bristol player at full-back for five of England's seven Grand Slams between 1913 and 1980. The Mem did not ever stage an international. By the time it was operative, England were firmly ensconced at Twickenham. Ashton Gate has staged both Tests played in Bristol, England v Wales in 1908 and All Blacks-Tonga during the 1999 World Cup.

But numerous touring teams visited, generally to play Western Counties. Australia were beaten three times - going down 9-8 in 1957 to a Western Counties team led by Blake, in 1967 by 9-0 to a team which included seven Bristol players and in 1988 by 26-10 to a South West Division select with four players from the host club.

The 1967 match against Australia came during a six-year spell in which all three major tourists were tested at the Mem. In 1963 the All Blacks fell behind by eight points to a Western Counties team which still led 8-3 at the break, retook the lead after an equalising try by the tourists and which finally fell honourably 22-14 after what Terry McLean recalled as "a delightful game, so delightful that the players at non-side fell into each others' arms in sheer pleasure at the fun of it all, and the spectators stood and clapped and clapped and clapped".

There were eight Bristol players in that team and seven in the XV who, after also leading at half-time, were held 3-3 by the Springboks on the last day of the 1960s, an afternoon characterised by 'intense cold and bitter cross-winds'. Two men, back rower David Rollitt - skipper against the Boks - and prolific wing Mike Collins, scorer of what McLean reckoned a 'princely' 40 yard try against the All Blacks, played in all three.

When the Mem did, late in life, get to stage an international match it was in rugby league - a memorable 32-20 victory by the USA over the Cook Islands in last year's World Cup, watched by a hugely appreciative audience of more than 7,000.

But of course the other sport that has in recent years helped define - and is now ending - the Mem's existence is football. Bristol Rovers, whose old Eastville ground, around a mile from the Mem, was turned into a supermarket in 1986, arrived a decade after that following an uneasy groundshare with Bath City.

Quite why somewhere that worked as a rugby ground never seemed quite right for football is probably a question for psychologists. But those misgivings seem to have been shared by football fans. One website for groundhoppers rates the Mem 75th out of 92 league grounds, albeit with praise for the pasties, and one posting comparing it to "a weird hybrid of a rugby ground and a golf club house".

Within two years of arriving the co-tenants had become landlords following Bristol Rugby's loss of Premiership status in 1998. Ever since then Bristol's fate - and that of the Mem - had been tied to Rovers' ambition to seek a new ground.

This isn't the first time fans have prepared to say goodbye - in 2007 Bristol were apparently destined for a groundshare across the Severn Bridge at Rodney Parade, Newport, but that Rovers blueprint fell through.

Recent years had seen considerable controversy over the ground's future. The memorial gates achieved listed status in 2011, while plans for the site - yet another supermarket - had been contested by a local campaign and a judicial review.

But now, it seems, the end is near. Bristol fans will hope their last game at the Mem has a happier outcome than that of the Rovers, who lost their league status after 94 years following a home defeat by Mansfield at the end of April. Some might regard that as just reward for turning two well-loved sporting venues into supermarkets.

The odds are against Bristol. A 19-point deficit will take some overturning against a tough, well-coached and resourceful Exiles team. But they'll not go quietly - the Mem has rarely, if ever, been quiet - and there'll be 93 years of fond memories fuelling Bristolian cheers when the teams run out for this characterful venue's final evening of rugby action come Wednesday.